PT - JOURNAL ARTICLE AU - V Hadzic AU - E Dervisevic AU - M Veselko TI - Concentric and eccentric strength profile of quadriceps and hamstrings in healthy volleyball players AID - 10.1136/bjsm.2011.084558.14 DP - 2011 May 01 TA - British Journal of Sports Medicine PG - 538--538 VI - 45 IP - 6 4099 - http://bjsm.bmj.com/content/45/6/538.1.short 4100 - http://bjsm.bmj.com/content/45/6/538.1.full SO - Br J Sports Med2011 May 01; 45 AB - Background Lower-extremity strength profile can be used in injury prevention, conditioning and rehabilitation of volleyball players. Objectives The goals were: (1) to describe the concentric and eccentric quadriceps (Q) and hamstrings (H) muscle function in volleyball players, (2) to evaluate the differences in Q and H strength, strength ratios and bilateral strength asymmetry among age groups, playing positions and playing levels, (3) to compare bilateral strength asymmetry in Q and H muscles in two different contraction modes. Design Controlled laboratory study. Setting Competitive elite level. Participants and intervention 95 professional male volleyball players were tested on an isokinetic machine at 60°/sec to assess concentric and eccentric Q and H strength. We also calculated strength ratios and bilateral strength asymmetries. Results Multivariate analysis of variances indicated significant main effect of playing level on relative PT (p=0.001) and strength ratios (p<0.05). International-level players had significantly (p<0.05) higher H strength and dynamic control ratio (DCR) of the right leg compared to the first and/or second national division players. There were no signs of bilateral strength asymmetry regardless of muscle group tested and contraction mode. Conclusions Our results suggest that right H strength and DCR could be important for successful volleyball performance. Descriptive data about Q and H muscle function can be used as guidelines for coaches and therapists during training and rehabilitation of male volleyball players.